This invention relates, in general, to devices for mounting structural elements together and for damping any vibration between these structural elements and relates, in particular, to a structurally damped bolt, as an axial load carrying member, with the desired load carrying capability in which a damping member is incorporated to produce the desired damping capability.
It is a primary object of this invention to provide an element of a structural system which has the required load carrying capability along with a much increased structural damping capability; such capability being in the order of ten percent or more of the coefficient of structural damping.
This invention is particularly useful for supporting, isolating, and damping mirrors having stringent optical performance requirements, where there are critical damping requirements, such as, in space structures, carbon optic mirrors, and other commercial applications such as diesel engine mounts, where the critical damping ratio needs to be higher than presently available and where size and bulk may be a problem.
Accordingly, it is still another object of this invention to provide a structural element as a basic building block for applications where size and bulk may be a problem and where a high damping ratio is required.
There are, of course, a number of prior art vibration damping devices, typical examples of which are shown in the U.S. Pat. to Inuzuka No. 4,121,813, to Jorn et al No. 4,007,924, to Hipsher No. 3,584,857, to Mendez No. 3,257,124, to Tiberghien No. 3,667,706, and to Peter No. 4,158,403. All of these patents are essentially bushings for impact absorbing and vibration damping between two bodies. None of these patents, however, are directed to a device as a basic building block of a structural system having an axial load carrying member with a damper in parallel arrangement therewith to produce a desired damping and load carrying capability.
Accordingly, it is still another object to this invention to improve the prior art damping devices and provide a structurally damped bolt with the required load carrying capability along with a much increased damping ability.